The objective of the Confocal Core Facility is to provide state-of-the-art instrumentation for examination of single living cells and tissues with submicron 3-dimensional resolution. The facility houses a Zeiss LSM 510 laser scanning confocal microscope equipped with multiple lasers to provide a variety of excitation lines. A tunable pulsed ThSapphire laser (700-900 nm) provides 200 femtosecond pulses for two and three-photon excitation of a variety of fluorophores whose one-photon excitation cross sections are in the ultra violet and visible light spectrum. An inverted Nikon Eclipse TE2000-S fluorescence microscope controlled by MetaMorph allows acquisition of wide-field fluorescence, bright field, and phase contrast images. The facility serves members of the Cancer Center, as well as the broader Case Western Reserve University community, and is open 7 days per week. Time on the instrument is by reservation only, and Cancer Center members will always have priority over nonmembers. The facility director has overall responsibility for the operations of the facility and provides expertise and consultation to core users in live cell confocal and multiphoton imaging. The facility manager has day-to-day responsibility for the microscopy component of the facility under the supervision of the director. An advisory committee meets annually to address any issues with facility operations, new technology development, and setting of policy. The advisory committee reports to the Senior Leaders Committee of the Cancer Center. The core is engaged in graduate teaching by organizing a 2-credit graduate course, Optical Microscopy and Imaging for Biologists. Students gain extensive hands-on training with state-of-the-art equipment for optical imaging guided by experienced academic instructors. Collectively, the Confocal Microscopy Core will have a large and positive impact on the Cancer Center's scientific programs. In addition, the use of the facility among different departments and centers will foster productive interactions between individual investigators to promote new collaborations.